# Blog

This started by tidying up some of the notes I took while working on audio/DSP stuff, but it's become a project of its own.

## Latest post

# Smooth Monotonic Interpolation

Geraint LuffProducing a smooth, *intuitive* curve from a set of control points.

I've been doing some GUI programming recently, and so here's a fun crossover between maths and user-interface problems.

## Investigations

Things I figured out up with while trying to solve a problem... or just having fun. 🙂

# Stride-Interpolated Delay

Geraint Luff originalWhen we change the length of a delay-line, we usually use either a smooth slide (with detuning) or a cross-fade (with comb-filtering artefacts). Let's look at a third option!

# Analytic pluck synthesis

Geraint Luff originalNo feedback, no wavetables, no aliasing: synthesising a plucked-string sound using a family of directly-computable band-limited impulses.

# A cheap energy-preserving-ish crossfade

Geraint Luff originalA fun little polynomial cross-fade curve with (almost) constant energy, extended into a family of curves for fractional power-laws.

## Writeups

Technical stuff I thought was interesting!

# Smooth Monotonic Interpolation

Geraint LuffProducing a smooth, *intuitive* curve from a set of control points.

# Invertible fixed-point complex rotation

Geraint LuffA look at how to perform lossless rotations on integer / fixed-point co-ordinates or complex values.

# Box-filters without accumulating errors

Geraint LuffSignalsmith Audio Ltd.

Exploring some ways to efficiently calculate box filters without accumulating floating-point errors, including varying-width filters.

# Extra-wide window functions

Geraint LuffWindow functions are typically matched to the length of your FFT, but they don't have to be. Let's look at how we can use a window longer than the FFT size.